Abstract:
Analog-to-digital converters (ADCs) convert analog
continuous time signals into discrete time, digital format. One
precondition that must be met for conventional nyquist rate ADCs is
that the input signal must be suitably band-limited to an input
bandwidth less than the nyquist frequency. This mandates expensive
anti-alias filters which contribute to system noise and distortion
degradation. By choosing an OSR of 2 and adopting simple linear
phase filtering techniques, significant inherent anti-alias
filtering is achieved, avoiding the need for an explicit anti-alias
filter in many applications. Additionally the proposed continuous
time input pipeline ADC eases a number of other challenges present
in conventional switched capacitor ADCs:- sampled opamp noise
folding, sampling distortion, reduced ADC area, switched-capacitor
pipeline ADC input loading. Chapter 2 introduces the first
continuous time input pipeline ADC in the literature. This ADC,
while providing significant benefits, does not provide the inherent
filtering. Chapter 3 presents the first continuous time input
pipeline ADC with inherent anti-alias filtering.
